Biological Science: Energy and Enzymes

This set of flashcards covers key concepts related to energy, enzymes, and metabolic pathways as discussed in the lecture notes.

What does the First Law of Thermodynamics state?

Energy is conserved; it cannot be created or destroyed, only transformed.

What are the two types of energy mentioned in the lecture?

Potential energy and kinetic energy.

What is entropy?

Entropy (S) is the measure of disorder in a system, and it always increases.

What differentiates spontaneous reactions from non-spontaneous reactions?

Spontaneous reactions release energy and disassemble molecules, while non-spontaneous reactions absorb or require energy to assemble molecules.

What is the role of enzymes in metabolic reactions?

Enzymes speed up chemical reactions by lowering the activation energy.

What factors regulate enzyme function and reaction rates?

Affinity for the substrate, temperature, pH, substrate concentration, enzyme concentration, and regulatory molecules.

What is energetic coupling?

Energetic coupling allows endergonic reactions to proceed using the free energy released from exergonic reactions.

What are redox reactions?

Redox reactions involve the transfer of electrons, where oxidation is losing electrons and reduction is gaining electrons.

How does ATP power cellular reactions?

ATP releases energy when its phosphate bonds are hydrolyzed, effectively powering endergonic reactions.

What happens to enzyme activity at suboptimal temperatures?

Enzyme activity decreases due to reduced collisions between enzyme and substrate.

What type of inhibition occurs when a product binds to an allosteric site?

Feedback inhibition.

What is competitive inhibition?

A type of enzyme inhibition where a molecule similar to the substrate competes for access to the active site.

How does substrate concentration affect reaction rates?

Increasing substrate concentration generally increases reaction rates until the enzyme becomes saturated.

What are cofactors and coenzymes?

Cofactors are non-protein molecules that assist enzyme function, while coenzymes are organic molecules that act as carriers of electrons or functional groups.

What does the First Law of Thermodynamics state?

Energy is conserved; it cannot be created or destroyed, only transformed.

What are the two types of energy mentioned in the lecture?

Potential energy and kinetic energy.

What is entropy?

Entropy (S) is the measure of disorder in a system, and it always increases.

What differentiates spontaneous reactions from non-spontaneous reactions?

Spontaneous reactions release energy and disassemble molecules, while non-spontaneous reactions absorb or require energy to assemble molecules.

What is the role of enzymes in metabolic reactions?

Enzymes speed up chemical reactions by lowering the activation energy.

What factors regulate enzyme function and reaction rates?

Affinity for the substrate, temperature, pH, substrate concentration, enzyme concentration, and regulatory molecules.

What is energetic coupling?

Energetic coupling allows endergonic reactions to proceed using the free energy released from exergonic reactions.

What are redox reactions?

Redox reactions involve the transfer of electrons, where oxidation is losing electrons and reduction is gaining electrons.

How does ATP power cellular reactions?

ATP releases energy when its phosphate bonds are hydrolyzed, effectively powering endergonic reactions.

What happens to enzyme activity at suboptimal temperatures?

Enzyme activity decreases due to reduced collisions between enzyme and substrate.

What type of inhibition occurs when a product binds to an allosteric site?

Feedback inhibition.

What is competitive inhibition?

A type of enzyme inhibition where a molecule similar to the substrate competes for access to the active site.

How does substrate concentration affect reaction rates?

Increasing substrate concentration generally increases reaction rates until the enzyme becomes saturated.

What are cofactors and coenzymes?

Cofactors are non-protein molecules that assist enzyme function, while coenzymes are organic molecules that act as carriers of electrons or functional groups.

What is Gibbs Free Energy (\Delta G)?

The energy available to do work in a system, which determines the spontaneity of a reaction.

What is activation energy (E_a)?

The minimum amount of energy required for a chemical reaction to proceed.

What is the active site of an enzyme?

The specific region on an enzyme where the substrate binds and catalysis occurs.

What is allosteric regulation?

Regulation of an enzyme's activity by the binding of a regulatory molecule at a site other than the active site.

What is an exergonic reaction?

A chemical reaction that releases free energy, meaning the products have less free energy than the reactants (\Delta G < 0).

What is an endergonic reaction?

A chemical reaction that absorbs free energy, meaning the products have more free energy than the reactants (\Delta G > 0) and requires energy input.